A Long Shadow over the Soul:
Molecular and Quantum Approaches to Psychopathology
An Interdisciplinary Dialog with Psychiatrists
FANO - March 2012

How mathematics can inform the diagnosis of mood disorders

At present day, the psychiatric diagnosis is performed without using any objective diagnostic tool, from the biological point of view. The Psychiatry seems to be one of the few areas of medicine, maybe the only one, which does not exercise any instrument and, often, technical diagnosis and therapy are entrusted to the psychiatrist experience.
There have been countless attempts and proposed solutions to this problem but there are not known methods, simple and economic, for clinical and practical use. However, the literature has suggested considering platelets as a key district.

From here the first idea, in 2005, to find a way that would look at the platelets in their entirety, to search for an approach that will resume their characteristics, their essence. The result was the idea of analyzing the fatty acid content of the membrane. The complexity of the membrane dynamics has also suggested the study by means of non-linear advanced analytical tools. In particular, it seemed more appropriate the use of an Artificial Neural Networks: the SOM (Self Organizing Map – Kohonen Network). This particular algorithm allows you to view the result graphically, building a two-dimensional map which places the subjects in a continuous way, not necessarily dichotomised.

There have been assessed, according to this approach, the membrane platelet fatty acids of a population of subjects with clinical diagnosis of Major Depression versus a population without the disease. The values of fatty acids of the 2 populations have been administered to the SOM, mixing healthy and pathological individuals and hidding the information on to their own pathological condition. As a result, the SOM was able to map the two populations using 3 specific fatty acids, recognizing as similar those belonging to the same population and, in the meanwhile, different those belonging to one population from the other ones.
The method proposed “photographs” the two populations, as they are, and tries to find commonalities and differences. Then it has been considered appropriate the choice of samples beyond age, sex, therapy. In fact, it was in the precise will of the two researchers, to build a method that could find a strong discriminating capacity within the study of the disease, further thousands possible under-classifications, that would have lead to limited scope results and, perhaps, misleading (with great probability they would have had results similar to ones already known).

The main goal of the method is not to find the biomarkers of a disease. Rather, it is to find differences between two populations “as they are” and to build an instrument with discriminating capacity, with a logic, whenever possible, not dichotomous, with the aim of creating a tool, really capable of doing clinical diagnosis. The direct task of finding bio-markers according to the rules given by the Evidence Based Medicine (EBM), requires the elimination of selection bias, and leads to a selectivity of a population often not likely, almost unreal, usually, clinically unrealistic.
Now, using the same method it has been possible to recognize the bipolar subjets from the depressive subjects.

In conclusion, the work done by Massimo Cocchi and Lucio Tonello deserves to be brought to international attention for having proposed a highly innovative method that is already giving a revolutionary contribution to the study of Major Depression and Bipolar Disorder, where, currently, there are not enough instruments in the hands of Clinicians.